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Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000. Example 1:Input: Output 阅读全文
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Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters. This 阅读全文
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Given an array consists of non-negative integers, your task is to count the number of triplets chosen from the array that can make triangles if we tak 阅读全文
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Design and implement a data structure for a compressed string iterator. It should support the following operations: next and hasNext. The given compre 阅读全文
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Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others are n 阅读全文